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1.
Chem Commun (Camb) ; 59(90): 13434-13437, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37847141

RESUMO

The improper disposal of hospital waste products containing genetic materials poses a serious safety threat. We present herein an environmentally friendly technology using a graphene-based novel carbon-allotropic surface to remediate such wastes. The used carbon-allotrope is decorated with an enediyne (EDE-1) enriched aromatic pi-conjugated structure to create an efficient and active surface for cleaving DNA strands. Under controlled exposure of ultraviolet (UV) radiation and heat, the developed surface influences genetic degradation without disturbing the bacterial populations present downstream of the water treatment system. The designed material has been extensively characterized using physicochemical and biological tools. Our results indicate that this approach can possibly be introduced in large scale hospital waste disposal streams for remediating genetic hazards and thereby developing a portable self-contained system.


Assuntos
Carbono , Grafite , Bactérias , DNA , Enedi-Inos
2.
J Biomed Opt ; 28(8): 082807, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37427335

RESUMO

Significance: Carbon dots (CDs) have attracted a host of research interest in recent years mainly due to their unique photoluminescence (PL) properties that make them applicable in various biomedical areas, such as imaging and image-guided therapy. However, the real mechanism underneath the PL is a subject of wide controversy and can be investigated from various angles. Aim: Our work investigates the effect of the isomeric nitrogen position as the precursor in the synthesis of CDs by shedding light on their photophysical properties on the single particles and ensemble level. Approach: To this end, we adopted five isomers of diaminopyridine (DAP) and urea as the precursors and obtained CDs during a hydrothermal process. The various photophysical properties were further investigated in depth by mass spectroscopy. CD molecular frontier orbital analyses aided us in justifying the fluorescence emission profile on the bulk level as well as the charge transfer processes. As a result of the varying fluorescent responses, we indicate that these particles can be utilized for machine learning (ML)-driven sensitive detection of oral microbiota. The sensing results were further supported by density functional theoretical calculations and docking studies. Results: The generating isomers have a significant effect on the overall photophysical properties at the bulk/ensembled level. On the single-particle level, although some of the photophysical properties such as average intensity remained the same, the overall differences in brightness, photo-blinking frequency, and bleaching time between the five samples were conceived. The various photophysical properties could be explained based on the different chromophores formed during the synthesis. Overall, an array of CDs was demonstrated herein to achieve ∼100% separation efficacy in segregating a mixed oral microbiome culture in a rapid (<0.5 h), high-throughput manner with superior accuracy. Conclusions: We have indicated that the PL properties of CDs can be regulated by the precursors' isomeric position of nitrogen. We emancipated this difference in a rapid method relying on ML algorithms to segregate the dental bacterial species as biosensors.


Assuntos
Corantes Fluorescentes , Pontos Quânticos , Corantes Fluorescentes/química , Carbono , Aminas , Imagem Óptica , Nitrogênio , Pontos Quânticos/química
3.
Artigo em Inglês | MEDLINE | ID: mdl-35975704

RESUMO

The lymphatic system is the first site of metastasis for most tumors and is a common reason for the failure of cancer therapy. The lymphatic system's anatomical properties make it difficult to deliver chemotherapy agents at therapeutic concentrations while avoiding systemic toxicity. Carbon nanoparticles offer a promising alternative for identifying and transporting therapeutic molecules. The larger diameter of lymphatic vessels compared to the diameter of blood vessels, allows carbon nanoparticles to selectively enter the lymphatic system once administered subcutaneously. Carbon nanoparticles stain tumor-draining lymph nodes black following intratumoral injection, making them useful in sentinel lymph node mapping. Drug-loaded carbon nanoparticles allow higher concentrations of chemotherapeutics to accumulate in regional lymph nodes while decreasing plasma drug accumulation. The use of carbon nanoparticles for chemotherapy delivery has been associated with lower mortality, fewer histopathology changes in vital organs, and lower serum concentrations of hepatocellular enzymes. This review will focus on the ability of carbon nanoparticles to target the lymphatics as well as their current and potential applications in sentinel lymph node mapping and oncology treatment regimens. This article is categorized under: Implantable Materials and Surgical Technologies > Nanoscale Tools and Techniques in Surgery.


Assuntos
Nanopartículas , Humanos , Metástase Linfática , Nanopartículas/química , Linfonodos/patologia , Corantes , Carbono
4.
Adv Sci (Weinh) ; 9(22): e2202414, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35657032

RESUMO

Small molecular NIR-II dyes are highly desirable for various biomedical applications. However, NIR-II probes are still limited due to the complex synthetic processes and inadequate availability of fluorescent core. Herein, the design and synthesis of three small molecular NIR-II dyes are reported. These dyes can be excited at 850-915 nm and emitted at 1280-1290 nm with a large stokes shift (≈375 nm). Experimental and computational results indicate a 2:1 preferable host-guest assembly between the cucurbit[8]uril (CB) and dye molecules. Interestingly, the dyes when self-assembled in presence of CB leads to the formation of nanocubes (≈200 nm) and exhibits marked enhancement in fluorescence emission intensity (Switch-On). However, the addition of red carbon dots (rCDots, ≈10 nm) quenches the fluorescence of these host-guest complexes (Switch-Off) providing flexibility in the user-defined tuning of photoluminescence. The turn-ON complex found to have comparable quantum yield to the commercially available near-infrared fluorophore, IR-26. The aqueous dispersibility, cellular and blood compatibility, and NIR-II bioimaging capability of the inclusion complexes is also explored. Thus, a switchable fluorescence behavior, driven by host-guest complexation and supramolecular self-assembly, is demonstrated here for three new NIR-II dyes.


Assuntos
Carbono , Corantes Fluorescentes , Fluorescência , Água
5.
Nanoscale Horiz ; 7(5): 533-542, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35311837

RESUMO

Gastrointestinal (GI) tract is one of the hard-to-reach target tissues for the delivery of contrast agents and drugs mediated by nanoparticles due to its harsh environment. Herein, we overcame this barrier by designing orally ingestible probiotic vectors for 'hitchhiking' ultrasmall hafnia (HfO2) (∼1-2 nm) nanoparticles. The minute-made synthesis of these nanoparticles is accomplished through a simple reduction reaction. These nanoparticles were incubated with probiotic bacteria with potential health benefits and were non-specifically taken up due to their small size. Subsequently, the bacteria were lyophilized and packed into a capsule to be administered orally as the radiopaque contrast agents for delineating the GI features. These nano-bio-hybrid entities could successfully be utilized as contrast agents in vivo in the conventional and multispectral computed tomography (CT). We demonstrated in 'color' the accumulated nanoparticles using advanced detectors of the photon counting CT. The enhanced nano-bio-interfacing capability achieved here can circumvent traditional nanoparticle solubility and delivery problems while offering a patient friendly approach for GI imaging to replace the currently practiced barium meal.


Assuntos
Nanopartículas , Probióticos , Humanos , Meios de Contraste , Trato Gastrointestinal/diagnóstico por imagem , Raios X
6.
Commun Biol ; 4(1): 846, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267305

RESUMO

Dental plaques are biofilms that cause dental caries by demineralization with acidogenic bacteria. These bacteria reside inside a protective sheath which makes any curative treatment challenging. We propose an antibiotic-free strategy to disrupt the biofilm by engineered clustered carbon dot nanoparticles that function in the acidic environment of the biofilms. In vitro and ex vivo studies on the mature biofilms of Streptococcus mutans revealed >90% biofilm inhibition associated with the contact-mediated interaction of nanoparticles with the bacterial membrane, excessive reactive oxygen species generation, and DNA fragmentation. An in vivo examination showed that these nanoparticles could effectively suppress the growth of S. mutans. Importantly, 16S rRNA analysis of the dental microbiota showed that the diversity and richness of bacterial species did not substantially change with nanoparticle treatment. Overall, this study presents a safe and effective approach to decrease the dental biofilm formation without disrupting the ecological balance of the oral cavity.


Assuntos
Biofilmes/efeitos dos fármacos , Microbiota/fisiologia , Nanopartículas/toxicidade , Polímeros/toxicidade , Streptococcus mutans/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Feminino , Humanos , Camundongos , Viabilidade Microbiana/efeitos dos fármacos , Microbiota/genética , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Células NIH 3T3 , Nanopartículas/química , Nanopartículas/ultraestrutura , Polímeros/química , RNA Ribossômico 16S/genética , Ratos Sprague-Dawley , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/ultraestrutura
7.
ACS Appl Mater Interfaces ; 12(9): 10183-10192, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32031773

RESUMO

Nanoscale fluorescent probes are of great importance due to their capabilities for imaging on multiscale. Herein, we report the first synthesis of structurally well-defined nanoparticulate "oligodots" developed for multicolor imaging in vitro and in vivo. These nanoparticles are prepared via condensation and curing reactions where the engineering of the solvent results in the nanoparticles with green (λem = 550 nm) and red (λem = 650 nm) emission range. Differences found in the photophysical properties have been attributed to variations in oligomeric compositions produced during the synthesis as was corroborated by extensive physicochemical characterizations. Specifically, mass spectroscopy provided a picture of the formed species during the synthesis. The feasibility of the oligodots for multicolor imaging is demonstrated both in vitro and in vivo. The red-emitting oligodot is employed for dynamic whole-body imaging in mice. It is envisioned that oligodots would enable multicolor imaging of various biomarkers in complex diseases such as cancer where numerous molecular and metabolic phenotypes work in concert in their emergence.


Assuntos
Corantes Fluorescentes/química , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Imagem Molecular/instrumentação , Imagem Molecular/métodos
8.
Biomaterials ; 228: 119542, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678842

RESUMO

Small bowel perforations and obstructions are relatively frequent surgical emergencies, are potentially life-threatening, and have multiple etiologies. In general, treatment requires urgent surgical repair or resection and at times can lead to further complications. Stents may be used to help with healing intestinal perforations but use is limited as currently available stents are non-absorbable, are manufactured in a narrow size range, and/or are limited to usage in locations that are accessible for endoscopic removal post-healing. The use of 3D-printed bioresorbable polymeric stents will provide patients with a stent that can prevent leakage, is tailored specifically to their geometry, and will be usable within the small bowel, which is not amenable to endoscopic stent placement. This work focused on the rapid manufacturing of gastrointestinal stents composed of a polycaprolactone-polydioxanone (PCL-PDO) composite. Dynamic Mechanical Analysis (DMA) tests were conducted to separately analyze the effects of composition, the filament formation process, and physiological temperature on the PCL-PDO material properties. The proposed stent design was then modeled using computer-aided design, and Finite Element Analysis (FEA) was used to simulate the effects of physiologically relevant forces on stent integrity. The presence of hydrolysable ester bonds was confirmed using FT-IR spectroscopy. In vitro studies were used to evaluate the biocompatibility of the polymer composite. Further analyses were conducted through stent placement in ex vivo pig intestines. PCL-PDO stents were then 3D-printed and placed in vivo in a pig model.


Assuntos
Trato Gastrointestinal , Stents , Animais , Análise de Elementos Finitos , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier , Suínos , Tomografia Computadorizada por Raios X
9.
ACS Nano ; 13(7): 7690-7704, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31246412

RESUMO

Photoacoustic imaging has emerged as a promising imaging platform with a high tissue penetration depth. However, biodegradable nanoparticles, especially those for photoacoustic imaging, are rare and limited to a few polymeric agents. The development of such nanoparticles holds great promise for clinically translatable diagnostic imaging with high biocompatibility. Metabolically digestible and inherently photoacoustic imaging probes can be developed from nanoprecipitation of biliverdin, a naturally occurring heme-based pigment. The synthesis of nanoparticles composed of a biliverdin network, cross-linked with a bifunctional amine linker, is achieved where spectral tuning relies on the choice of reaction media. Nanoparticles synthesized in water or water containing sodium chloride exhibit higher absorbance and lower fluorescence compared to nanoparticles synthesized in 2-(N-morpholino)ethanesulfonic acid buffer. All nanoparticles display high absorbance at 365 and 680 nm. Excitation at near-infrared wavelengths leads to a strong photoacoustic signal, while excitation with ultraviolet wavelengths results in fluorescence emission. In vivo photoacoustic imaging experiments in mice demonstrated that the nanoparticles accumulate in lymph nodes, highlighting their potential utility as photoacoustic agents for sentinel lymph node detection. The biotransformation of these agents was studied using mass spectroscopy, and they were found to be completely biodegraded in the presence of biliverdin reductase, a ubiquitous enzyme found in the body. Degradation of these particles was also confirmed in vivo. Thus, the nanoparticles developed here are a promising platform for biocompatible biological imaging due to their inherent photoacoustic and fluorescent properties as well as their complete metabolic digestion.


Assuntos
Biliverdina/química , Linfonodos/diagnóstico por imagem , Nanopartículas/química , Imagem Óptica , Técnicas Fotoacústicas , Animais , Biliverdina/síntese química , Biliverdina/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Hidrodinâmica , Células MCF-7 , Camundongos , Camundongos Nus , Nanopartículas/metabolismo , Tamanho da Partícula , Propriedades de Superfície , Suínos
10.
ACS Appl Mater Interfaces ; 11(20): 18074-18089, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31013055

RESUMO

Transcription factor STAT3 has been shown to regulate genes that are involved in stem cell self-renewal and thus represents a novel therapeutic target of great biological significance. However, many small-molecule agents with potential effects through STAT3 modulation in cancer therapy lack aqueous solubility and high off-target toxicity, hence impeding efficient bioavailability and activity. This work, for the first time, reports a prodrug-based strategy for selective and safer delivery of STAT3 inhibitors designed toward metastatic and drug-resistant breast cancer. We have synthesized a novel lipase-labile SN-2 phospholipid prodrug from a clinically investigated STAT3 inhibitor, nifuroxazide (Pro-nifuroxazide), which can be regioselectively cleaved by the membrane-abundant enzymes in cancer cells. Pro-nifuroxazide self-assembled to sub 20 nm nanoparticles (NPs), and the cytotoxic ability was screened in ER(+)-MCF-7 and ER(-)-MD-MB231 cells at 48-72 h using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetra-zolium bromide proliferation assay. Results indicated that Pro-nifuroxazide NPs are multifold more effective toward inhibiting cancer cells in a time-dependent manner compared to parent nifuroxazide. A remarkable improvement in the local concentration of drugs to as high as ∼240 fold when assembled into NPs is presumably the reason for this functional improvement. We also introduced molecular dynamics simulations to generate Pro-nifuroxazide nano-assembly, as a model assembly from triggerable anti-cancer drugs, to provide molecular insights correlating physicochemical and anti-cancer properties. In silico properties of Pro-nifuroxazide including size, chemistry of NPs and membrane interactions with individual molecules could be validated by in vitro functional activities in cells of breast cancer origin. The in vivo anti-cancer efficiencies of Pro-nifuroxazide NPs in nude mice xenografts with MCF-7 revealed remarkable growth inhibition of as high as 400%. Histopathological analysis corroborated these findings to show significantly high nuclear fragmentation and retracted cytoplasm. Immunostaining on tumor section demonstrated a significantly lower level of pSTAT-3 by Pro-nifuroxazide NP treatment, establishing the inhibition of STAT-3 phosphorylation. Our strategy for the first time proposes a translatable prodrug agent self-assembled into NPs and demonstrates remarkable enhancement in IC50, induced apoptosis, and reduced cancer cell population through STAT-3 inhibition via reduced phosphorylation.


Assuntos
Antineoplásicos , Hidroxibenzoatos , Nanomedicina , Neoplasias , Nitrofuranos , Pró-Fármacos , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Humanos , Hidroxibenzoatos/química , Hidroxibenzoatos/farmacocinética , Hidroxibenzoatos/farmacologia , Células MCF-7 , Camundongos , Camundongos Nus , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Nitrofuranos/química , Nitrofuranos/farmacocinética , Nitrofuranos/farmacologia , Pró-Fármacos/química , Pró-Fármacos/farmacocinética , Pró-Fármacos/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Med Chem ; 61(23): 10739-10752, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30375864

RESUMO

Sarcomas are rare and heterogeneous cancer variants of mesenchymal origin. Their genetic heterogeneity coupled with uncertain histogenesis makes them difficult to treat and results in poor prognosis. In this work, we show that structure-based drug discovery involving computational modeling can be used to identify a new retinoid X receptor (RXR) agonist ligand with a bis(indolyl)methane scaffold. This agent co-self-assembles with an amphiphilic diblock copolymer resulting in nanoparticles (Nano-RXR) with excellent kinetic stability, which were evaluated for efficacy and safety in transformed sarcoma cells, 63-3 Cre and 141-10 Cre of pig origin, and in rodent xenograft models. Responses at gene and protein levels established the treatment approach as a highly effective RXR agonist across cell, rodent, and "Oncopig" models. Interestingly, Nano-RXR was not only able to modulate metabolic and transporter genes related to orphan nuclear receptors but also played a major role in modulating programmed cell death in sarcomas developed in Oncopigs.


Assuntos
Desenho de Fármacos , Indóis/síntese química , Indóis/farmacologia , Receptores X de Retinoides/agonistas , Sarcoma/metabolismo , Animais , Linhagem Celular Tumoral , Técnicas de Química Sintética , Progressão da Doença , Humanos , Interações Hidrofóbicas e Hidrofílicas , Indóis/química , Indóis/uso terapêutico , Modelos Moleculares , Nanopartículas/química , Receptores Ativados por Proliferador de Peroxissomo/genética , Conformação Proteica , Receptores X de Retinoides/química , Receptores X de Retinoides/metabolismo , Sarcoma/tratamento farmacológico , Sarcoma/patologia , Suínos , Ativação Transcricional/efeitos dos fármacos
12.
ACS Appl Mater Interfaces ; 10(44): 37886-37897, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30300544

RESUMO

Targeting the DNA of tumor cells with small molecules may offer effective clinical strategies for transcriptional inhibition. We unveil synthesis and characterization of ∼20 nm chiral carbon nanoparticles for enantiospecific recognition of DNA. Our approach inculcates chirality in carbon nanoparticles by controlled tethering of minor groove binders, i.e., Tröger's base (TB). The chiral particles positively enriched the cellular nucleus in MCF-7 breast cancer cells, irrespective of the TB asymmetry tethered on the particle surface, but negatively induced chiral carbon nanoparticles exhibited improved efficiency at inhibiting cell growth. Further studies indicated that these chiral particles act as nanotweezers to perturb the genomic DNA and induce apoptosis cascade in cancer cells.


Assuntos
Proliferação de Células/efeitos dos fármacos , DNA/isolamento & purificação , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Carvão Vegetal/química , DNA/química , Dano ao DNA/efeitos dos fármacos , Humanos , Células MCF-7 , Nanopartículas/química , Neoplasias/patologia , Estereoisomerismo
13.
Bioconjug Chem ; 29(11): 3913-3922, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30352502

RESUMO

Manipulating the chiroptical properties at the nanoscale is of great importance in stereoselective reactions, enantioseparation, self-assembly, and biological phenomena. In recent years, carbon dots have garnered great attention because of their favorable properties such as tunable fluorescence, high biocompatibility, and facile, scalable synthetic procedures. Herein, we report for the first time the unusual behavior of cyclic amino acids on the surface of carbon dots prepared via microwave-based carbonization. Various amino acids were introduced on the surface of carbon dots via EDC/NHS conjugation at room temperature. Circular dichroism results revealed that although most of the surface conjugated amino acids can preserve their chirality on negatively charged, "bare" carbon dots, the "handedness" of cyclic α-amino acids can be flipped when covalently attached on carbon dots. Moreover, these chiroptical carbon dots were found to interact with the cellular membrane or its mimic in a highly selective manner due to their acquired asymmetric selectivity. A comprehensive inhibitor study was conducted to investigate the pathway of cellular trafficking of these carbon dots. Overall, it was concluded that the chirality of the amino acid on the surface of carbon dots could regulate many of the cellular processes.


Assuntos
Aminoácidos/química , Carbono/química , Pontos Quânticos/química , Aminoácidos/metabolismo , Carbono/metabolismo , Dicroísmo Circular , Ciclização , Endocitose , Humanos , Células MCF-7 , Micro-Ondas , Modelos Moleculares , Pontos Quânticos/metabolismo , Pontos Quânticos/ultraestrutura , Estereoisomerismo , Propriedades de Superfície
14.
ACS Omega ; 3(6): 6378-6387, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30221233

RESUMO

Tubulin polymerization is critical in mitosis process, which regulates uncontrolled cell divisions. Here, we report a new class of pyrene-pyrazole pharmacophore (PPP) for targeting microtubules. Syntheses of seven pyrenyl-substituted pyrazoles with side-chain modification at N-1 and C-3 positions of the pyrazole ring were accomplished from alkenyl hydrazones via C-N dehydrogenative cross-coupling using copper catalyst under aerobic condition. Tubulin polymerization with PPPs was investigated using docking and biological tools to reveal that these ligands are capable of influencing microtubule polymerization and their interaction with α-, ß-tubulin active binding sites, which are substituent specific. Furthermore, cytotoxicity response of these PPPs was tested on cancer cells of different origin, such as MCF-7, MDA-MB231, and C32, and also noncancerous normal cells, such as MCF-10A. All newly synthesized PPPs showed excellent anticancer activities. The anticancer activities and half-maximal inhibitory concentration (IC50) values of all PPPs across different cancer cell lines (MCF-7, MDA-MB231, and C32) have been demonstrated. 1,3-Diphenyl-5-(pyren-1-yl)-1H-pyrazole was found to be best among all other PPPs in killing significant population of all of the cancerous cell with IC50 values 1 ± 0.5, 0.5 ± 0.2, and 5.0 ± 2.0 µM in MCF-7, MDA-MB231, and C32 cells, respectively.

15.
Biomaterials ; 181: 252-267, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30096560

RESUMO

The removal of tenacious dental plaque is of paramount importance; however, early diagnosis can be a challenging task in dental clinics due to the limitations of current approaches, specifically X-ray-based techniques. We have approached this problem by integrating antibacterial properties and X-ray contrast enhancement in a single probe specific to colonies of Streptococcus mutans as the most predominant and carious oral bacteria. We report the synthesis of an inherently therapeutic polymeric silane conjugated hafnium oxide nanoparticles (Hf PS NPs). Using a high-affinity pathogen-selective peptide, the concept of molecularly targeted X-ray imaging of cariogenic pathogen S. mutans was demonstrated. Ex vivo studies using extracted human tooth demonstrated striking X-ray attenuation of NPs vs. tooth. Additionally, Hf PS NPs exhibited significant bactericidal properties against cariogenic pathogen. Electron microscopy revealed that the antibacterial activity occurred via a 'latch and kill' mechanism. Mechanistic studies determined that these NPs fragmented bacterial DNA components to exert their antimicrobial effect. Importantly, Hf PS NPs effectively inhibited the growth of a mature biofilm on an ex vivo human tooth model. Finally, the NPs were applied to the rodent model of dental biofilm. Topical administration of the Hf PS NPs for 8 days (1X daily) could effectively attenuate the S. mutans biofilm challenge. This report is the first of its kind to demonstrate that HfO2-based NPs can be used for simultaneous diagnosis and antibacterial treatment without requiring an additional drug.


Assuntos
Háfnio/química , Nanopartículas/química , Óxidos/química , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/patogenicidade , Animais , Biofilmes/efeitos dos fármacos , Feminino , Espectrometria de Massas , Plasmídeos/genética , Ratos , Ratos Sprague-Dawley , Infecções Estreptocócicas/tratamento farmacológico
16.
ACS Appl Mater Interfaces ; 10(23): 19408-19415, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29757601

RESUMO

Phosphonated compounds, in particular, bisanalogs are widely applied in clinical settings for the treatment of severe bone turnovers and recently as imaging probes when conjugated with organic fluorophores. Herein, we introduce a bone seeking luminescent probe that shows a high binding affinity toward bone minerals based on monophosphonated carbon dots (CDs). Spheroidal CDs tethered with PEG monophosphates are synthesized in a one-pot hydrothermal method and are physicochemically characterized, where the retention of phosphonates is confirmed by 13P NMR and X-ray photoelectron spectroscopy. Interestingly, the high abundance of multiple monodentate phosphonates exhibited strong binding to hydroxyapatite, the main bone mineral constituent. The remarkable optophysical properties of monophosphonated CDs were confirmed in an ex vivo model of the bovine cortical bone where the imaging feasibility of microcracks, which are calcium-rich regions, was demonstrated. The in vivo studies specified the potential application of monophosphonated CDs for imaging when injected intramuscularly. The biodigestible nature and cytocompatibility of the probe presented here obviate the demand for a secondary fluorophore, while offering a nanoscale strategy for bone targeting and can eventually be employed for potential bone therapy in the future.


Assuntos
Osso e Ossos , Animais , Carbono , Bovinos , Corantes Fluorescentes , Luminescência , Espectroscopia Fotoeletrônica , Pontos Quânticos
17.
Chem Rec ; 18(6): 619-658, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29465807

RESUMO

A major proportion of basic cause for human cancer has been linked to widespread environmental pollutants including analogs of polyarenes. Search of an effective therapy can be started with the understanding of the generation of such "carcinogens" and their biological interactions. This review is to discuss the syntheses, structural activities, mechanistic and biological studies of polyarenes such as polycyclic aromatic hydrocarbons (PAHs), polycyclic azaarenes (PAAs) and their thia-analogs (PASH). It also summarizes the mechanism of mutagenicity and tumorigenicity via metabolic interventions producing diol epoxide complexes and eventually formation of DNA adducts. It suggests that inhibition of oxidative reactions and formation of diols and epoxides and unspecific intracellular activation of cytochrome P450 enzymes could be approaches in therapy against such mutagenicity and tumorigenicity. Thus, this review reflects that understanding of molecular mechanisms and activations along with a clinical and translational medicine approach would require achieving both prevention and treatment of this atrocity.


Assuntos
Carcinogênese/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/síntese química , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Álcoois/síntese química , Álcoois/química , Sistema Enzimático do Citocromo P-450/metabolismo , Compostos de Epóxi/síntese química , Compostos de Epóxi/química , Humanos , Estresse Oxidativo/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/química , Relação Estrutura-Atividade
18.
ACS Appl Mater Interfaces ; 9(25): 21147-21154, 2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28581711

RESUMO

Spheroidal nanoparticles of algal ("phytonic") origin were synthesized and composed of carbonaceous architectures and surface-rich oxygenated functional groups. Nanoparticles were negatively charged and efficiently luminescent after ultraviolet-range excitation and called as "photophytonic" nanoparticles. A multitude of analytical techniques confirmed the rich profusion of hydroxyl, carboxylate, and amines at the nanoscale, while spectroscopic investigation indicated the presence of α-amines, a signature functionality present in amino acids. Confirmed via a series of biological assays, i.e., growth regression, antimigration, and protein-regression studies, photophytonic nanoparticles serendipitously revealed remarkable anticancer activity against various stages of breast cancer cells, barring the need for an encapsulated drug. We report that nanoparticles derived from algal biomass exhibit intrinsic antimigratory properties against cancer, likely due to the rich abundance of α-amino acids.


Assuntos
Nanopartículas , Aminoácidos , Biomassa , Humanos , Neoplasias
19.
ACS Appl Mater Interfaces ; 9(13): 11528-11536, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28291324

RESUMO

The nanoparticles (NPs) that contain the therapeutic agent within themselves without further modifications can be coined as "self-therapeutic" NPs. The development of these agents especially when derived from natural resources can lead to a paradigm shift in the field of cancer nanotechnology as they can immensely facilitate the complex chemistry procedures and the follow up biological complications. Herein, we demonstrate that inherently therapeutic NPs "integrating" ß-carotene can be synthesized from Dunaliella salina microalgae in a single step without complicated chemistry. The facile synthesis involved microwave irradiation of aqueous suspension of algae which resulted in water dispersible NPs with hydrodynamic diameter of ∼80 nm. Subsequently, extensive physiochemical characterizations were performed to confirm the integrity of the particles. The pro-oxidant activities of the integrated ß-carotene were triggered by photoexcitation under UV lamp (362 nm). It was demonstrated that after UV exposure, the C32 human melanoma cells incubated with NPs experienced extensive cell death as opposed to nonilluminated samples. Further cellular analysis revealed that the significant reactive oxygen species (ROS) and in particular singlet oxygen were responsible for the cells' damage while the mode of cell death was dominated by apoptosis. Moreover, detailed endocytic inhibition studies specified that UV exposure affected NPs' cellular uptake mechanism. These inherently therapeutic NPs can open new avenues for melanoma cancer treatment via ROS generation in vitro.


Assuntos
Nanopartículas , Humanos , Lagos , Microalgas , Nanotecnologia , Espécies Reativas de Oxigênio
20.
Adv Healthc Mater ; 6(11)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28322012

RESUMO

Patients with percutaneous coronary intervention generally receive either bare metal stents or drug-eluting stents to restore the normal blood flow. However, due to the lack of stent production with an individual patient in mind, the same level of effectiveness may not be possible in treating two different clinical scenarios. This study introduces for the first time the feasibility of a patient-specific stenting process constructed from direct 3D segmentation of medical images using direct 3D printing of biodegradable polymer-graphene composite with dual drug incorporation. A biodegradable polymer-carbon composite is prepared doped with graphene nanoplatelets to achieve controlled release of combinatorics as anticoagulation and antirestenosis agents. This study develops a technology prototyped for personalized stenting. An in silico analysis is performed to optimize the stent design for printing and its prediction of sustainability under force exerted by coronary artery or blood flow. A holistic approach covering in silico to in situ-in vivo establishes the structural integrity of the polymer composite, its mechanical properties, drug loading and release control, prototyping, functional activity, safety, and feasibility of placement in coronary artery of swine.


Assuntos
Implantes Absorvíveis , Plásticos Biodegradáveis/química , Stents Farmacológicos , Grafite/química , Teste de Materiais , Nanopartículas/química , Impressão Tridimensional , Animais , Vasos Coronários/metabolismo , Vasos Coronários/patologia , Vasos Coronários/cirurgia , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Intervenção Coronária Percutânea , Suínos
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